The immunobiology of virus-lymphocyte interactions is under investigation in an effort to further understand mechanisms of recovery and tissue injury in influenza viral disease. Receptors on lymphocytes for several influenza virus strains will be studied using purified virus labeled with I125. Labeled virus will also be used to differentiate mouse lymphoid cell subpopulations on the basis of receptors for influenza A viruses. The results will be correlated with the pattern of alteration in immune function induced by these viruses. Other experiments will involve delineating the role of T cells in recovery from influenza. Using an experimental model of influenza pneumonia in mice, experiments will be performed to determine the origin, class, and function of lymphocytes which infiltrate pulmonary tissue during the infection. BIBLIOGRAPHIC REFERENCES: Woodruff, J.F. and J.J. Woodruff, 1975. Interaction of myxo-and paramyxoviruses with murine lymphocytes. In the Immune System and Infectious Diseases, E. Neter and F. Milgrom, eds, 4th Int. Convoc. Immunol., Buffalo, N,Y., 1974(Karger, Basel), pp. 118-129. Woodruff, J.F.and J.J. Woodruff, 1975. T lymphocyte interaction with viruses and virus-infected tissues, Progr. Med. Virol., 19;120.